About

Brachychiton rupestris (commonly known as the narrow-leaved bottle tree or Queensland bottle tree) is a tree in the family Malvaceae, endemic to the Australian state of Queensland. Described by Sir Thomas Mitchell and John Lindley in 1848, it earned its name from its bulbous trunk, which can be up to 3.5 metres (11 ft) in diameter at breast height (DBH). Reaching around 10–25 m (33–82 ft) high, the Queensland bottle tree is deciduous, losing its leaves seasonally, between September and December. The leaves are simple or divided, with one or more narrow leaf blades up to 11 centimetres (4 in) long and 2 cm (0.8 in) wide. Cream-coloured flowers appear from September to November, and are followed by woody, boat-shaped follicles that ripen from November to May. No subspecies are recognised.

As a drought deciduous and succulent tree, much like the baobab (Adansonia) of Madagascar, B.

How to grow it

Bottle trees are commonly found planted in streets and parks, on farms, and as features in gardens. An avenue in Roma, Queensland, was planted between 1918 and 1920, each tree representing one of 93 local men killed in World War I. The species has been cultivated as an indoor plant and a bonsai subject.

Bottle trees grow best in well-drained, slightly acidic soil, in full sunshine. They are suited to cultivation in regional climates equivalent to USDA hardiness zones 9 to 12. In the first stages of growth, the bottle tree is very slow-growing, and the formation of the unique bottle shape is not visible until the tree is about 5 to 8 years old. Mature trees transplant easily, and can withstand intervals of up to three months between digging and replanting without detriment. Bottle trees grown from seed may take up to 20 years to flower. Flowering takes place after adult leaves have appeared.

Where it grows

Brachychiton rupestris is found in central Queensland from latitude 22° S to 28° S, with the western limits of its range defined by the 500 mm rainfall isohyet. It grows on the tops and slopes of hills or ridges in low hilly country, in clay, shale, or basalt soils. It is an emergent tree in forests dominated by brigalow (Acacia harpophylla), hoop pine (Araucaria cunninghamii), or ooline (Cadellia pentastylis). It is always present in the Central semi-evergreen vine thicket—also known as Bottletree Scrub—of the Brigalow Belt. Other common species include broad-leaved bottle tree (Brachychiton australis) and belah (Casuarina cristata). The narrow-leaved bottle tree is replaced by the kurrajong in similar communities in New South Wales.

Uses

Aboriginal people made use of the trees through eating the roots of young plants and by consuming secretions from the trunk that were induced by wounds. Fibre obtained from the species was used to make nets. The leaves have also been used for fodder, and Queensland farmers often leave bottle trees as a potential food source when land is cleared. During drought conditions, whole trees have been felled to feed stock. The soft edible pulp inside the trunk is exposed by removing the bark. The pulp is energy-rich but protein-poor, and occasional cases of nitrate poisoning have led to cattle deaths.

Other Brachychiton plants

Illawarra Flame Tree · Brachychiton acuminatus · Brachychiton albidus · Broadleaf Bottletree · Little Kurrajong · Kurrajong · Brachychiton chrysocarpus · Brachychiton compactus · Pink flame tree · Northern Kurrajong · Brachychiton fitzgeraldianus · Brachychiton garrawayae